Tan, E. (1980). Sampling considerations for diseases with low prevelence [microform]. Photoduplication Service. University of the Philippines Library.
Dyfyniad Arddull ChicagoTan, Elizabeth. Sampling Considerations for Diseases with Low Prevelence [microform]. Quezon City: Photoduplication Service. University of the Philippines Library, 1980.
Dyfyniad MLATan, Elizabeth. Sampling Considerations for Diseases with Low Prevelence [microform]. Photoduplication Service. University of the Philippines Library, 1980.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.